It has been a warm and muggy start to the meteorological autumn for many, with a high of 30C in southeast England.
The heat and humidity brought some lively thunderstorms too, but many places were dry.
Monday will bring more widespread heavy showers or longer spells of rain, with further thundery downpours likely.
Check the five-day forecast where you live
Britons enjoyed a warm first day of meteorological autumn – but forecasters warned not to expect a repeat of last year. Pic: PA
England, east Wales, and eastern Scotland look most at risk of thunderstorms.
The Met Office has issued another thunderstorm warning for those areas, with 30-40mm of rain possible in less than an hour – and perhaps as much as 80mm.
Localised surface water flooding is possible, with frequent lightning and hail.
Tuesday looks fresher but there will be further showers, although they should be lighter than Monday.
From the middle of the week, it looks like northern areas will be mainly dry, while southern parts will keep the risk of showers.
Increasing heat and humidity into the weekend in the south may bring the chance of thunderstorms again.
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Into the following week, settled conditions could become more widespread – but only a few days ago this week was looking more settled so things may change.
From around the middle of the month, a mobile westerly wind is more likely, with spells of wind and rain possible.
Northern and western parts are likely to be wettest, while the south and east are set to be driest.
But that is a long way off meteorologically speaking.
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Long-range forecasts in early autumn can be especially tricky due to influences across the Atlantic.
We’re now into the peak of the Atlantic hurricane season, so any storms that develop will influence our weather patterns, although for now it’s relatively quiet.
But the US National Hurricane Center (NHC) is monitoring a low chance of tropical development this week.
That said, it is unlikely to have any significant influence on the UK weather for some time, if at all.
Either way, the UK is unlikely to experience record-breaking conditions like last September.
The first half of September 2023 saw high pressure dominating and a significant heatwave.
Temperatures exceeded 30C somewhere in the UK on seven consecutive days, which was a September record.
And 33.5C was recorded on 10 September, which was the highest temperature of 2023.
Since records began, only four other years have seen the UK’s highest temperature in September, they were in 2016, 1954, 1949, and 1919.